Core Excitation in a Stripping Reaction

${}_{}{}^{44}{}_{}{}^{}\mathrm{Ca}(d, p){}_{}{}^{45}{}_{}{}^{}\mathrm{Ca}$ stripping, corresponding to the various excited states of ${}_{}{}^{45}{}_{}{}^{}\mathrm{Ca}$, has been calculated by including the effect of excitation of the $2^{+}$ state of the ${}_{}{}^{44}{}_{}{}^{}\mathrm{Ca}$ core in the stripping process. In this calculation, the term appearing in the stripping amplitude from the protoncore residual interaction has been retained, and its effect has been found to be quite important. It has been concluded that in the cases where the stripping cross section is very small, the usual distorted-wave Born-approximation analysis, which ignores the above effect, may lead one to incorrect conclusions. On the whole, our calculated cross sections show some of the so-called nonstripping features which have been recently observed in a large number of stripping experiments.